Telmisartan attenuates diabetic nephropathy by mitigating oxidative stress and inflammation, and upregulating Nrf2/HO-1 signaling in diabetic rats

Rosmarinic acid protects against cyclophosphamide-induced hepatotoxicity via inhibition of oxidative stress, inflammation, and apoptosis and upregulation of Nrf2 in mice

Cyclophosphamide (CP) is widely used in chemotherapy to treat various types of cancer. However, it is toxic to the liver and other organs. Rosmarinic acid (RA) possesses anti-inflammatory, antioxidant, and cytoprotective properties. This study investigated the protective effects of RA against CP-induced liver injury in mice. Mice were treated with RA (25, 50, and 100 mg/kg) for 15 days and followed by a single injection of CP on day 16th. CP injection resulted in an elevation in serum AST, ALT, and ALP, along with multiple histopathological alterations in the liver. CP also induced increased levels of MDA and NO, associated with declined GSH, SOD and CAT. RA pretreatment prevented liver injury, alleviated the enhanced levels of MDA and NO, and restored antioxidants defenses, hence avoiding the oxidative injury in the liver. Moreover, RA pretreatment attenuated NF-κB p65 and proinflammatory cytokines levels. Liver of CP-injected mice also showed a decrease in Bcl2, accompanied with elevated BAX and caspase-3 expression, an effect that RA pretreatment alleviated. In addition, pretreatment of CP-administrated mice with RA restored the Nrf2 expression in the liver. Taken together, this study suggests a potential application value of RA in preventing CP hepatotoxicity and sheds light on the possible mechanism.

Diallyl disulfide prevents cadmium-induced testicular injury by attenuating oxidative stress, apoptosis, and TLR-4/NF-κB and JAK1/STAT3 signaling and upregulating SIRT1 in rats

BACKGROUND

Cadmium (Cd) is a heavy metal environmental pollutant that can cause serious health problems. Cd can cause structural changes in the testes and exposure to this heavy metal is associated with the loss of sperms and male infertility. The role of oxidative stress and inflammation in Cd toxicity has been acknowledged. Diallyl disulfide (DADS), an organo-sulfur compound found in garlic, possesses antioxidant, anti-inflammatory, and cytoprotective effects. This study evaluated the protective effect of DADS against Cd reproductive toxicity in male rats, emphasizing the involvement of redox imbalance, TLR-4/NF-κB and JAK1/STAT3 signaling, and SIRT1.

METHODS

DADS (10 mg/kg body weight) was administered orally to rats for 14 days and a single dose of Cd (1.2 mg/kg) was injected intraperitoneally on day 7. Blood and samples from the testes were collected for analysis.

RESULTS

Cd caused testicular injury manifested by multiple histopathological changes and loss of sperms from seminiferous tubules. Circulating levels of gonadotropins and testosterone were decreased in Cd-administered rats. DADS prevented Cd-induced testicular injury and ameliorated serum levels of gonadotropins and testosterone. Cd increased testicular reactive oxygen species (ROS) and malondialdehyde (MDA) and upregulated TLR-4, NF-κB, pro-inflammatory cytokines, JAK1 and STAT3 phosphorylation, Bax and caspase-3, while decreased antioxidants and Bcl-2. DADS effectively decreased ROS and MDA, downregulated TLR-4, NF-κB, JAK1, STAT3, pro-inflammatory cytokines and pro-apoptosis markers in Cd-administered rats. In addition, DADS enhanced antioxidants, Bcl-2, SIRT1 and cytoglobin in the testis of Cd-administered rats.

CONCLUSION

DADS prevents Cd-induced testicular injury by attenuating oxidative stress, apoptosis, and TLR-4/NF-κB and JAK1/STAT3 signaling, and upregulating SIRT1 and antioxidants.

Effect of Hibiscus sabdariffa L. leaf flavonoid-rich extract on Nrf-2 and HO-1 pathways in liver damage of streptozotocin-induced diabetic rats

This study investigated the effects of flavonoid-rich extract from Hibiscus sabdariffa L. (Malvaceae) leaves on liver damage in streptozotocin-induced diabetic rats by evaluating various biochemical parameters, including the molecular gene expressions of Nrf-2 and HO-1 as well as histological parameters. The extract was found to significantly reduce liver damage, as evidenced by lower levels of fragmented DNA and protein carbonyl concentrations. Oxidative stress markers, including malondialdehyde (MDA) level, were also significantly (p < 0.05) decreased, while antioxidant biomarkers, like reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione-S-transferase (GST) were enhanced. Additionally, the extract improved the activities of key liver enzymes, including phosphatases and transaminases, and increased albumin levels. Importantly, the study demonstrated that H. sabdariffa extract effectively regulated the expression of Nrf-2 and HO-1, suggesting a significant role in mitigating liver damage. These findings highlight its potential as a therapeutic agent for liver protection in diabetic conditions.

Mechanistic insights on the role of Nrf-2 signalling in Huntington's disease

BACKGROUND

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder affecting individuals worldwide. It is characterized by progressive motor dysfunction, cognitive decline, and psychiatric disturbances. The pathogenesis of HD involves oxidative stress, neuroinflammation, and mitochondrial dysfunction. Nuclear factor erythroid 2-related factor 2 (Nrf2), a key transcription factor regulating cellular responses to redox imbalance and inflammation, has emerged as a potential target for therapeutic intervention.

METHODS

Through the use of a number of different search engines like Scopus, PubMed, Elsevier and Bentham, a literature review was carried out with the keywords 'Huntington's Disease, 'Pathology of HD' and 'Nrf2 signalling pathway'. Using the keywords that were given above, this review was carried out in order to collect the most recent publications and gain an understanding of the breadth of the extensive research that has been conducted on the role of Nrf2 in HD pathogenesis.

RESULTS

Oxidative stress and neuroinflammation significantly contribute to HD progression. Activation of Nrf2 offers neuroprotection by enhancing anti-oxidant defense mechanisms. Furthermore, several signaling pathways, play crucial roles in HD pathophysiology. Pharmacological modulation of these pathways through selective inhibitors or agonists shows promise for the development of new therapeutic strategies.

CONCLUSION

The various downstream pathways such as extracellular signal-related kinase (ERK), phosphoinositide 3-Kinase (PI3-K), 5'-AMP-activated protein kinase (AMPK), Sirtuins, Mitogen-activated protein kinases (MAPK) plays a role in alleviating pathophysiology of HD. Diverse reports of these studies demonstrated PI3-K/AMPK/ERK/Sirtuins activators and MAPK inhibitors as encouraging targets in alleviating HD pathophysiology.

Crosstalk of Hyperglycaemia and Cellular Mechanisms in the Pathogenesis of Diabetic Kidney Disease

Among all nephropathies, diabetic kidney disease (DKD) is the most common cause of kidney impairment advancement to end-stage renal disease (ESRD). Although DKD has no cure, the disease is commonly managed by strict control of blood glucose and blood pressure, and in most of these cases, kidney function often deteriorates, resulting in dialysis, kidney replacement therapy, and high mortality. The difficulties in finding a cure for DKD are mainly due to a poor understanding of the underpinning complex cellular mechanisms that could be identified as druggable targets for the treatment of this disease. The review is thus aimed at giving insight into the interconnection between chronic hyperglycaemia and cellular mechanistic perturbations of nephropathy in diabetes. A comprehensive literature review of observational studies on DKD published within the past ten years, with 57 percent published within the past three years was carried out. The article search focused on original research studies and reviews published in English. The articles were explored using Google Scholar, Medline, Web of Science, and PubMed databases based on keywords, titles, and abstracts related to the topic. This article provides a detailed relationship between hyperglycaemia, oxidative stress, and various cellular mechanisms that underlie the onset and progression of the disease. Moreover, it also shows how these mechanisms affect organelle dysfunction, resulting in fibrosis and podocyte impairment. The advances in understanding the complexity of DKD mechanisms discussed in this review will expedite opportunities to develop new interventions for treating the disease.

Effective protective mechanisms of HO-1 in diabetic complications: a narrative review

Diabetes mellitus is a metabolic disorder with persistent hyperglycemia caused by a variety of underlying factors. Chronic hyperglycemia can lead to diverse serious consequences and diversified complications, which pose a serious threat to patients. Among the major complications are cardiovascular disease, kidney disease, diabetic foot ulcers, diabetic retinopathy, and neurological disorders. Heme oxygenase 1 (HO-1) is a protective enzyme with antioxidant, anti-inflammatory and anti-apoptotic effects, which has been intensively studied and plays an important role in diabetic complications. By inducing the expression and activity of HO-1, it can enhance the antioxidant, anti-inflammatory, and anti-apoptotic capacity of tissues, and thus reduce the degree of damage in diabetic complications. The present study aims to review the relationship between HO-1 and the pathogenesis of diabetes and its complications. HO-1 is involved in the regulation of macrophage polarization and promotes the M1 state (pro-inflammatory) towards to the M2 state (anti-inflammatory). Induction of HO-1 expression in dendritic cells inhibits them maturation and secretion of pro-inflammatory cytokines and promotes regulatory T cell (Treg cell) responses. The induction of HO-1 can reduce the production of reactive oxygen species, thereby reducing oxidative stress and inflammation. Besides, HO-1 also has an important effect in novel programmed cell death such as pyroptosis and ferroptosis, thereby playing a protective role against diabetes. In conclusion, HO-1 plays a significant role in the occurrence and development of diabetic complications and is closely associated with a variety of complications. HO-1 is anticipated to serve as a novel target for addressing diabetic complications, and it holds promise as a potential therapeutic agent for diabetes and its associated complications. We hope to provide inspiration and ideas for future studies in the mechanism and targets of HO-1 through this review.

Haloxylon salicornicum Phytochemicals Suppress NF-κB, iNOS and Pro-inflammatory Cytokines in Lipopolysaccharide-induced Macrophages

Haloxylon salicornicum is traditionally used for the treatment of several disorders associated with inflammation. Despite it is a defense response against tissue injury and infections, inflammation can become a chronic condition that can negatively impact the body. This study investigated the effect of H. salicornicum phytochemicals nuclear factor-kappaB (NF-κB), inducible nitric oxide synthase (iNOS) and cytokines release by lipopolysaccharide (LPS)-challenged macrophages in vitro. The binding affinity of the tested phytochemical towards NF-κB and iNOS was investigated using molecular docking. Ten compounds (four coumarins, three sterols and three flavonoids) were isolated from the ethanolic extract of H. salicornicum. Treatment of LPS-challenged macrophages with the compounds resulted in remarkable decrease in NF-κB p65 and iNOS mRNA abundance. All compounds suppressed the production of nitric oxide (NO) and the pro-inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-6) from macrophages challenged with LPS. Molecular docking revealed the ability of the isolated phytochemicals to bind NF-κB p65 and iNOS. In conclusion, H. salicornicum is a rich source of phytochemicals with anti-inflammatory properties. The anti-inflammatory efficacy of H. salicornicum phytoconstituents is mediated via their ability to modulate NF-κB and iNOS, and suppress the release of NO, TNF-α, and IL-6 from macrophages.

Targeting NADPH Oxidase as an Approach for Diabetic Bladder Dysfunction

Diabetic bladder dysfunction (DBD) is the most prevalent complication of diabetes mellitus (DM), affecting >50% of all patients. Currently, no specific treatment is available for this condition. In the early stages of DBD, patients typically complain of frequent urination and often have difficulty sensing when their bladders are full. Over time, bladder function deteriorates to a decompensated state in which incontinence develops. Based on studies of diabetic changes in the eye, kidney, heart, and nerves, it is now recognized that DM causes tissue damage by altering redox signaling in target organs. NADPH oxidase (NOX), whose sole function is the production of reactive oxygen species (ROS), plays a pivotal role in other well-known and bothersome diabetic complications. However, there is a substantial gap in understanding how NOX controls bladder function in health and the impact of NOX on DBD. The current review provides a thorough overview of the various NOX isoforms and their roles in bladder function and discusses the importance of further investigating the role of NOXs as a key contributor to DBD pathogenesis, either as a trigger and/or an effector and potentially as a target.

Galangin attenuates chlorpyrifos-induced kidney injury by mitigating oxidative stress and inflammation and upregulating Nrf2 and farnesoid-X-receptor in rats

Chlorpyrifos (CPF) is a highly toxic commonly used pesticide and can seriously harm human health. This study assessed the potential of galangin (GAL), an antioxidant flavonoid, to attenuate oxidative stress, inflammation and kidney injury caused by CPF, emphasizing the role of farnesoid-x-receptor (FXR) and Nrf2. Rats were supplemented with CPF and GAL for 28 days. CPF increased serum creatinine, urea and Kim-1, provoked several tissue alterations, and increased kidney ROS, malondialdehyde (MDA), NF-κB p65, TNF-α, iNOS, and caspase-3. GAL effectively ameliorated serum kidney injury markers, ROS, MDA, and TNF-α, suppressed NF-κB p65, iNOS, and caspase-3, and enhanced antioxidants. GAL suppressed Keap1 and upregulated FXR, Nrf2, HO-1 and NQO-1 in CPF-administered rats. GAL exhibited binding affinity with Keap1, FXR, caspase-3, iNOS, HO-1, and NF-κB. In conclusion, GAL is effective in preventing CPF nephrotoxicity by attenuating oxidative stress and inflammation. This protection is linked to upregulation of antioxidants, Nrf2/HO-1 signaling and FXR.

Unraveling the Potential of Saccharum officinarum and Chlorella vulgaris towards 5-Fluorouracil-Induced Nephrotoxicity in Rats

5-Fluorouracil (5-FU) is often used as a chemotherapeutic agent in treating tumors and is said to have adverse effects, including nephrotoxicity. Therefore, the present study aimed to evaluate the protective effects of Chlorella vulgaris (VL) and Saccharum officinarum L. (SOL) against 5-FU-induced nephrotoxicity in rats through the measurement of renal histology, kidney damage indicators, and antioxidant measures. A total of forty-eight male rats were allotted into six groups: group 1 acted as a control negative group (control), group 2 received 5-FU and worked as a control positive group (FU), group 3 received SOL 15 mL/kg (SOL), group 4 received VL 400 mg/kg (VL), group 5 received 5-FU+SOL (5-FU+SOL), and group 6 received 5-FU+VL (5-FU+VL). After fifteen days, blood and renal tissue specimens were collected for hematological, biochemical, molecular, and histopathological examinations. Findings of the current investigation showed that 5-FU leads to hematological alterations and kidney injury evinced by elevated serum concentrations of uric acid, creatinine, and urea (p < 0.01), and a marked increase in kidney MDA and NO levels with a reduction in kidney CAT, SOD and GSH activities (p < 0.05). Alterations of the histopathological structure of kidney tissue in the FU group were noticed compared to the other groups. 5-FU administration elevated expression levels of TNF-α, lipocalin 2, and KIM1 (p < 0.01) compared to the control ones. 5-FU-induced nephrotoxicity was ameliorated after treatment with SOL and VL via their free radical scavenging, potent antioxidant, and anti-inflammatory effects. In conclusion, our findings demonstrate that the treatment with SOL and VL significantly improved nephrotoxicity induced by 5-FU in rats.

Ameliorative effect of Metformin / alpha-lipoic acid combination on diabetic nephropathy via modulation of YAP/ miR-29a/PTEN/p-AKT axis

Diabetic nephropathy (DN) is the most frequent and serious complication of type 2 diabetes (T2DM). Lack of a precise remedy and socio-economic burden of DN patients implements searching about alternative therapies. This study aims to evaluate the possible beneficial effect of alpha-lipoic acid (α-LA) alone or in combination with metformin (Met) in ameliorating STZ/High fat diet (HFD)-induced DN. T2DM was induced via HFD administration for 15 weeks and single ip injection of STZ (35 mg/kg) at week 7. Male Sprague-Dawley rats were randomly grouped as follows: control group, STZ/HFD-induced DN, Met/T; daily treated with 150 mg/kg Met, α-LA/T group; daily treated with 100 mg/kg α-LA, and Met/T + α-LA/T group; daily treated with Met and α-LA at same doses. Administration of Met and α-LA succeeded in attenuating STZ/HFD-induced DN as manifested by significant decrease in kidney weight as well as renal and cardiac hypertrophy index. Moreover, Met and α-LA improved glycemic control, kidney functions and lipid profile as well as restored redox balance. Additionally, Met and α-LA administration significantly upregulated PTEN level accompanied by significant downregulation in renal p-AKT and miR-29a levels. Histopathologically, Met and α-LA administration mitigated STZ/HFD-induced histopathological alterations in kidney and heart. Moreover, immunohistochemical examination revealed a significant decrease in renal YAP, collagen I and Ki-67. Taken together, these observations revealed that Met and α-LA administration could protect against STZ/HFD-induced DN.

Telmisartan ameliorates nephropathy and restores the hippo pathway in rats with metabolic syndrome

The main objective of this study was to determine if the telmisartan-ameliorative effects of metabolic syndrome (MetS)-evoked nephropathy are attributed to the Hippo pathway. A secondary objective was to investigate the potential of vitamin D3 to enhance telmisartan-favourable effects. A diet composed of 24% fat and 3% salt, along with drinking water containing 10% fructose, was administered for 12 weeks to induce MetS. MetS-rats were given telmisartan (5 mg/kg/day), vitamin D3 (10 μg/kg/day) or both by gavage, starting in the sixth week of experimental diet administration. Assessments performed at closure included renal function, histological examination, catalase, malondialdehyde (MDA), nuclear factor kappa-B (NF-κB), interleukin-6 (IL-6), peroxisome proliferator-activated receptor-γ (PPAR-γ), phosphatase and tensin homolog (PTEN), and transforming growth factor-β (TGF-β). Matrix metalloproteinase-9 (MMP-9) immunostaining was conducted. The expression of the Hippo pathway components, as well as that of angiotensin II type 1 and type 2 (AT1 and AT2), receptors was evaluated. Telmisartan attenuated MetS-evoked nephropathy, as demonstrated by improvement of renal function and histological features, enhancement of catalase, reduction of MDA, inflammation (NF-κB, IL-6), and renal fibrosis (increased PPAR-γ and PTEN and reduced MMP-9 and TGF-β). Telmisartan downregulated AT1-receptor, upregulated AT2-receptor and restored the Hippo pathway. Vitamin D3 replicated most of the telmisartan-elicited effects and enhanced the antifibrotic actions of telmisartan. The alleviative effects of telmisartan on MetS-evoked nephropathy may be related to the restoration of the Hippo pathway. The combination of vitamin D3 and telmisartan exerted more favourable effects on metabolic and nephropathic biomarkers compared with either one administered alone.

Berberine attenuates inflammation and oxidative stress and modulates lymphocyte E-NTPDase in acute hyperlipidemia

Hyperlipidemia is a common clinically encountered health condition worldwide that promotes the development and progression of cardiovascular diseases, including atherosclerosis. Berberine (BBR) is a natural product with acknowledged anti-inflammatory, antioxidant, and metabolic effects. This study evaluated the effect of BBR on lipid alterations, oxidative stress, and inflammatory response in rats with acute hyperlipidemia induced by poloxamer-407 (P-407). Rats were pretreated with BBR (25 and 50 mg/kg) for 14 days and acute hyperlipidemia was induced by a single dose of P-407 (500 mg/kg). BBR ameliorated hypercholesterolemia, hypertriglyceridemia, and plasma lipoproteins in P-407-adminsitered rats. Plasma lipoprotein lipase (LPL) activity was decreased, and hepatic 3-hydroxy-3-methylglutaryl CoA (HMG-CoA) reductase activity was enhanced in hyperlipidemic rats. The expression of low-density lipoprotein receptor (LDL-R) and ATP-binding cassette transporter 1 (ABCA1) was downregulated in hyperlipidemic rats. BBR enhanced LPL activity, upregulated LDL-R, and ABCA1, and suppressed HMG-CoA reductase in P-407-administered rats. Pretreatment with BBR ameliorated lipid peroxidation, nitric oxide (NO), pro-inflammatory mediators (interleukin [IL]-6, IL-1β, tumor necrosis factor [TNF]-α, interferon-γ, IL-4 and IL-18) and enhanced antioxidants. In addition, BBR suppressed lymphocyte ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase) and ecto-adenosine deaminase (E-ADA) as well as NO and TNF-α release by macrophages isolated from normal and hyperlipidemic rats. In silico investigations revealed the binding affinity of BBR toward LPL, HMG-CoA reductase, LDL-R, PSK9, ABCA1, and E-NTPDase. In conclusion, BBR effectively prevented acute hyperlipidemia and its associated inflammatory responses by modulating LPL, cholesterolgenesis, cytokine release, and lymphocyte E-NTPDase and E-ADA. Therefore, BBR is an effective and safe natural compound that might be employed as an adjuvant against hyperlipidemia and its associated inflammation.

Simvastatin mitigates diabetic nephropathy by upregulating farnesoid X receptor and Nrf2/HO-1 signaling and attenuating oxidative stress and inflammation in rats

Diabetic nephropathy is one of the complications of diabetes that affects the kidney and can result in renal failure. The cholesterol-lowering drug simvastatin (SIM) has shown promising effects against diabetic nephropathy (DN). This study evaluated the protective role of SIM on DN, pointing to the involvement of farnesoid X receptor (FXR) and Nrf2/HO-1 signaling in attenuating inflammatory response, oxidative injury, and tissue damage in streptozotocin-induced diabetic rats. SIM was supplemented orally for 8 weeks, and samples were collected for analysis. SIM effectively ameliorated hyperglycemia, kidney hypertrophy, body weight loss, and tissue injury and fibrosis in diabetic animals. SIM mitigated oxidative stress (OS), inflammatory response, and cell death, as evidenced by the suppressed malondialdehyde, nitric oxide, myeloperoxidase, NF-kB, TNF-α, IL-1β, CD68, Bax, and caspase-3 in the diabetic kidney. These effects were linked to suppressed Keap1, upregulated FXR, Nrf2, and HO-1, and enhanced antioxidant defenses and Bcl-2. The in silico findings revealed the binding affinity of SIM with NF-kB, caspase-3, Keap1, HO-1, and FXR. In conclusion, SIM protects against DN by attenuating hyperglycemia, kidney injury, fibrosis, inflammation, and OS, and upregulating antioxidants, FXR, and Nrf2/HO-1 signaling.

Pioglitazone attenuates tamoxifen-induced liver damage in rats via modulating Keap1/Nrf2/HO-1 and SIRT1/Notch1 signaling pathways: In-vivo investigations, and molecular docking analysis

BACKGROUND

Tamoxifen (TAM) is a chemotherapeutic drug widely utilized to treat breast cancer. On the other hand, it exerts deleterious cellular effects in clinical applications as an antineoplastic agent, such as liver damage and cirrhosis. TAM-induced hepatic toxicity is mainly attributed to oxidative stress and inflammation. Pioglitazone (PIO), a peroxisome proliferator-activated receptor-gamma (PPAR-γ) agonist, is utilized to treat diabetes mellitus type-2. PIO has been reported to exert anti-inflammatory and antioxidant effects in different tissues. This research assessed the impact of PIO against TAM-induced hepatic intoxication.

METHODS

Rats received PIO (10 mg/kg) and TAM (45 mg/kg) orally for 10 days.

RESULTS

TAM increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT), triggered several histopathological alterations, NF-κB p65, increased hepatic oxidative stress, and pro-inflammatory cytokines. PIO protects against TAM-induced liver dysfunction, reduced malondialdehyde (MDA), and pro-inflammatory markers along with improved hepatic antioxidants. Moreover, PIO, increased hepatic Bcl-2 expression while reducing Bax expression and caspase-3 levels. In addition, PIO decreased Keap-1, Notch1, and Hes-1 while upregulated HO-1, Nrf2, and SIRT1. Molecular docking showed the binding affinity of PIO for Keap-1, NF-κB, and SIRT1.

CONCLUSION

PIO mitigated TAM hepatotoxicity by decreasing apoptosis, inflammation, and oxidative stress. The protecting ability of PIO was accompanied by reducing Keap-1 and NF-κB and regulating Keap1/Nrf2/HO-1 and Sirt1/Notch1 signaling. A schematic diagram illustrating the protective effect of PIO against TAM hepatotoxicity. PIO prevented TAM-induced liver injury by regulating Nrf2/HO-1 and SIRT1/Notch1 signaling and mitigating oxidative stress, inflammation, and apoptosis.

The melatonin receptor agonist agomelatine protects against acute pancreatitis induced by cadmium by attenuating inflammation and oxidative stress and modulating Nrf2/HO-1 pathway

Pancreatitis is a serious effect of the heavy metal cadmium (Cd) and inflammation and oxidative stress (OS) are implicated in Cd-induced pancreatic injury. This study evaluated the effect of the melatonin receptor agonist agomelatine (AGM) on Cd-induced acute pancreatitis (AP), pointing to its modulatory effect on inflammation, OS, and Nrf2/HO-1 pathway. Rats were supplemented with AGM orally for 14 days and a single injection of cadmium chloride (CdCl2) on day 7. Cd increased serum amylase and lipase and caused pancreatic endocrine and exocrine tissue injury. Malondialdehyde (MDA), nitric oxide (NO) and myeloperoxidase (MPO) were elevated, nuclear factor (NF)-kB p65, inducible NO synthase (iNOS), interleukin (IL)-6, tumor necrosis factor (TNF)-α and CD40 were upregulated, and antioxidants were decreased in the pancreas of Cd-administered rats. AGM ameliorated serum amylase and lipase and pancreatic OS, NF-kB p65, CD40, pro-inflammatory mediators and caspase-3, prevented tissue injury and enhanced antioxidants. AGM downregulated Keap1 and enhanced Nrf2 and HO-1 in the pancreas of Cd-administered rats. In silico findings revealed the binding affinity of AGM with Keap1, HO-1, CD40L and caspase-3. In conclusion, AGM protected against AP induced by Cd by preventing inflammation, OS and apoptosis and modulating Nrf2/HO-1 pathway.

Interference of periostin attenuates pathological changes, proinflammatory markers and renal fibrosis in diabetic kidney injury

BACKGROUND

Diabetic nephropathy (DN) is a prevalent complication of diabetes, in which inflammation and fibrosis are the significant pathogenesis. Periostin is a matricellular protein that functions on stabilizing the extracellular matrix by binding to integrins during development. This study aimed to explored the role of periostin in DN.

METHODS

The animal and cell models of DN were constructed in streptozocin (STZ)-induced mice and high glucose-challenged human mesangial cells (HMCs). The role of periostin in pathological changes, inflammation and fibrosis in DN was investigated through biochemical detection, HE and Masson staining and scores, western blot, enzyme‑linked immunosorbent assay (ELISA) and real-time quantitative PCR (RT-qPCR) assays.

RESULTS

Knockdown of periostin counteracted the STZ-induced the ratio of kidney weight and body weight, and the concentrations of urine albumin excretion (UAE), serum creatinine (Scr), urine albumin/creatinine ratio (UACR) and blood urea nitrogen (BUN) in mice. Moreover, silencing of periostin alleviated the pathological manifestations and reduced the concentrations of IL-6, TNF-α and IL-1β in mice kidney tissues and sera. Also, downregulation of periostin decreased the relative protein expression of fibronectin, collagen IV and α-SMA in kidney tissues. Meanwhile, interference of periostin attenuated the levels of pro-inflammation factors and the expressions of fibrosis markers in HG-induced HMCs.

CONCLUSION

Interference of periostin resisted DN via attenuating the pro-inflammatory cytokines release and renal fibrosis in diabetic kidney injury. Our study establishes a basis for its further study and underlying application in clinical practice in diagnosing and treating diabetic kidney injury or other relevant diseases.

Multi-target action of Garcinia livingstonei extract and secondary metabolites against fatty acid synthase, α-glucosidase, and xanthine oxidase

Garcinia livingstonei is a traditional herbal medicine that showed beneficial health effects and bioactivities. Four compounds have been isolated from the plant leaves and were elucidated as lupeol, betulin, podocarpusflavone A, and amentoflavone. The inhibitory activities of G. livingstonei extract and isolated metabolites against fatty acid synthase (FAS), α-glucosidase, and xanthine oxidase (XO) were investigated in vitro. The affinity of the compounds toward the studied enzymes was investigated in silico. The plant extract inhibited FAS, α-glucosidase, and XO with IC50 values of 26.34, 67.88, and 33.05 µg/mL, respectively. Among the isolated metabolites, betulin exhibited the most inhibitory activity against α-glucosidase and XO with IC50 values of 38.96 and 30.94 µg/mL, respectively. Podocarpusflavone A and betulin were the most potent inhibitors of FAS with IC50 values of 24.08 and 27.96 µg/mL, respectively. Computational studies corroborated these results highlighting the interactions between metabolites and the enzymes. In conclusion, G. livingstonei and its constituents possess the potential to modulate enzymes involved in metabolism and oxidative stress.

Cadmium cardiotoxicity is associated with oxidative stress and upregulated TLR-4/NF-kB pathway in rats; protective role of agomelatine

Cardiotoxicity is one of the hazardous effects of the exposure to the heavy metal cadmium (Cd). Inflammation and oxidative injury are implicated in the cardiotoxic mechanism of Cd. The melatonin receptor agonist agomelatine (AGM) showed promising effects against oxidative and inflammatory responses. This study evaluated the effect of AGM on Cd-induced cardiotoxicity in rats, pointing to its modulatory effect on TLR-4/NF-kB pathway and HSP70. Rats received AGM for 14 days and a single dose of Cd on day 7 and blood and heart samples were collected for analyses. Cd increased serum CK-MB, AST and LDH and caused cardiac tissue injury. Cardiac malondialdehyde (MDA), nitric oxide (NO) and MPO were elevated and GSH, SOD and GST decreased in Cd-administered rats. AGM ameliorated serum CK-MB, AST and LDH and cardiac MDA, NO and MPO, prevented tissue injury and enhanced antioxidants. AGM downregulated serum CRP and cardiac TLR-4, NF-kB, iNOS, IL-6, TNF-α and COX-2 in Cd-administered rats. HSP70 was upregulated in the heart of Cd-challenged rats treated with AGM. In silico findings revealed the binding affinity of AGM with TLR-4 and NF-kB. In conclusion, AGM protected against Cd cardiotoxicity by preventing myocardial injury and oxidative stress and modulating HSP70 and TLR-4/NF-kB pathway.

Diabetic Nephropathy: Significance of Determining Oxidative Stress and Opportunities for Antioxidant Therapies

Diabetes mellitus (DM) belongs to the category of socially significant diseases with epidemic rates of increases in prevalence. Diabetic nephropathy (DN) is a specific kind of kidney damage that occurs in 40% of patients with DM and is considered a serious complication of DM. Most modern methods for treatments aimed at slowing down the progression of DN have side effects and do not produce unambiguous positive results in the long term. This fact has encouraged researchers to search for additional or alternative treatment methods. Hyperglycemia has a negative effect on renal structures due to a number of factors, including the activation of the polyol and hexosamine glucose metabolism pathways, the activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, the accumulation of advanced glycation end products and increases in the insulin resistance and endothelial dysfunction of tissues. The above mechanisms cause the development of oxidative stress (OS) reactions and mitochondrial dysfunction, which in turn contribute to the development and progression of DN. Modern antioxidant therapies for DN involve various phytochemicals (food antioxidants, resveratrol, curcumin, alpha-lipoic acid preparations, etc.), which are widely used not only for the treatment of diabetes but also other systemic diseases. It has also been suggested that therapeutic approaches that target the source of reactive oxygen species in DN may have certain advantages in terms of nephroprotection from OS. This review describes the significance of studies on OS biomarkers in the pathogenesis of DN and analyzes various approaches to reducing the intensity of OS in the prevention and treatment of DN.

Adipose-derived stem cell exosomes regulate Nrf2/Keap1 in diabetic nephropathy by targeting FAM129B

BACKGROUND

Exosomes from adipose-derived stem cells (ADSCs-Exos) have exhibited a therapeutic role in diabetic nephropathy (DN). Further studies are needed to investigate how ADSCs-Exos regulate oxidative stress and inflammation in high glucose-induced podocyte injury.

METHODS

An enzyme-linked immunosorbent assay (ELISA) was used to detect cellular inflammation. Reactive oxygen species (ROS) levels were assessed using flow cytometry in podocytes with different treatments. A malondialdehyde (MDA) kit was used to evaluate the lipid peroxidation levels in podocytes and kidney tissues of mice. Western blotting and co-immunoprecipitation were performed to detect protein expression and protein-protein interactions.

RESULTS

ADSCs-Exos reversed oxidative stress and inflammation in podocytes and kidney tissues of DN mice induced by high glucose levels in vitro and in vivo. Interference with heme oxygenase-1 expression could reverse the improvement effect of ADSCs-Exos on oxidative stress induced by high glucose levels. Furthermore, high glucose inhibited nuclear factor erythroid 2-related factor 2 (Nrf2) protein expression and promoted Kelch-like ECH-associated protein 1 (Keap1) protein expression in podocytes, as well as their binding ability. As a potential target for Nrf2/Keap1 pathway regulation, FAM129B expression in podocytes is regulated by high glucose and ADSCs-Exos. Moreover, FAM129B siRNA blocked the inhibitory effect of ADSCs-Exos on intracellular ROS and MDA upregulation induced by high glucose in podocytes.

CONCLUSION

ADSCs-Exos regulate the Nrf2/Keap1 pathway to alleviate inflammation and oxidative stress in DN by targeting FAM129B, which may provide a potential therapeutic strategy for DN.

The protective effect of 7-hydroxycoumarin against cisplatin-induced liver injury is mediated via attenuation of oxidative stress and inflammation and upregulation of Nrf2/HO-1 pathway

Cisplatin (CIS) is an effective chemotherapy against different solid cancers. However, the adverse effects, including hepatotoxicity, limit its clinical use. 7-hydroxycoumarin (7-HC) possesses antioxidant and hepatoprotective activities, but its protective effect against CIS hepatotoxicity has not been investigated. This study evaluated the effect of 7-HC on liver injury, oxidative stress (OS), and inflammation provoked by CIS. Rats received 7-HC (25, 50, and 100 mg/kg) orally for 2 weeks followed by intraperitoneal injection of CIS (7 mg/kg) at day 15. CIS increased serum transaminases, alkaline phosphatase (ALP), and bilirubin and provoked tissue injury accompanied by elevated reactive oxygen species (ROS), malondialdehyde (MDA), and nitric oxide (NO). Liver nuclear factor (NF)-κB p65, inducible NO synthase (iNOS), pro-inflammatory cytokines, Bax, and caspase-3 were upregulated, and antioxidant defenses and Bcl-2 were decreased in CIS-treated rats, while 7-HC prevented liver injury and ameliorated OS, inflammatory and apoptosis markers. In addition, 7-HC enhanced nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase (HO)-1 in CIS-administered rats and in silico studies revealed its binding affinity toward HO-1. In conclusion, 7-HC protected against CIS hepatotoxicity by mitigating OS and inflammatory response and modulating Nrf2/HO-1 pathway.

Exploration of Artemisinin Against IgA Nephropathy via AKT/Nrf2 Pathway by Bioinformatics and Experimental Validation

Background

Artemisinin (ART) is a safe and effective antimalarial drug. In recent years, antimalarial drugs have demonstrated a good therapeutic efficacy in IgA nephropathy, suggesting that this may become a new treatment option.

Purpose

We aimed to evaluate the effect and mechanism of artemisinin in IgA nephropathy.

Methods

In this study, CMap database was used to predict the artemisinin therapeutic effect for IgA nephropathy. A network pharmacology approach was applied to explore the unknown mechanism of artemisinin in IgA nephropathy. We used molecular docking to predict the binding affinity of artemisinin with the targets. A mouse model of IgA nephropathy was established to investigate the therapeutic effect of artemisinin on IgA nephropathy. In vitro, the cell counting Kit-8 assay was used to evaluate the cytotoxicity of artemisinin. Flow cytometry and PCR assays were used to detect the effects of artemisinin on oxidative stress and fibrosis in lipopolysaccharide (LPS)-stimulated mesangial cells. Western blot and immunofluorescence were used to detect the expression of pathway proteins.

Results

CMap analysis showed artemisinin may reverse the expression levels of differentially expressed genes in IgA nephropathy. Eighty-seven potential targets of artemisinin in the treatment of IgA nephropathy were screened. Among them, 15 hub targets were identified. Enrichment analysis and GSEA analysis indicated that response to reactive oxygen species is the core biological process. AKT1 and EGFR had the highest docking affinity with artemisinin. In vivo, artemisinin could improve renal injury and fibrosis in mice. In vitro, artemisinin attenuated LPS-induced oxidative stress and fibrosis promoted AKT phosphorylation and Nrf2 nuclear translocation.

Conclusion

Artemisinin reduced the level of fibrosis and oxidative stress with IgA nephropathy through the AKT/Nrf2 pathway, which provided an alternative treatment for IgAN.

Limonin ameliorates cardiovascular dysfunction and remodeling in hypertensive rats

AIMS

Limonin is a tetracyclic triterpenoid isolated from citrus fruits. Here, the effects of limonin on cardiovascular abnormalities in nitric oxide-deficient rats induced by N^ω-Nitrol-arginine methyl ester (L-NAME) were explored.

MAIN METHODS

Male Sprague Dawley rats were given L-NAME (40 mg/kg, drinking water) for 3 weeks and then treated daily with polyethylene glycol (vehicle), limonin (50 or 100 mg/kg) or telmisartan (10 mg/kg) for two weeks.

KEY FINDINGS

Limonin (100 mg/kg) markedly reduced L-NAME-induced hypertension, cardiovascular dysfunction and remodeling in rats (P < 0.05). Increases in systemic angiotensin-converting enzyme (ACE) activity and angiotensin II (Ang II) and a reduction in circulating ACE2 were restored in hypertensive rats treated with limonin (P < 0.05). Reductions in antioxidant enzymes and nitric oxide metabolites (NOx) and increases in oxidative stress components induced by L-NAME were relieved by limonin treatment (P < 0.05). Limonin suppressed the increased expression of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in cardiac tissue and circulating TNF-α in rats that received L-NAME (P < 0.05). Changes in Ang II receptor type I (AT1R), Mas receptor (MasR), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB) and NADPH oxidase subunit 2 (gp91^phox) protein expression in cardiac and aortic tissue were normalized by limonin (P < 0.05).

SIGNIFICANCE

In conclusion, limonin ameliorated L-NAME-induced hypertension, cardiovascular dysfunction and remodeling in rats. These effects were relevant to restorations of the renin-angiotensin system, oxidative stress and inflammation in NO-deficient rats. The molecular mechanisms are associated with the modulation of AT1R, MasR, NF-ĸB and gp91^phox protein expression in cardiac and aortic tissue.

Nrf2 signaling in diabetic nephropathy, cardiomyopathy and neuropathy: Therapeutic targeting, challenges and future prospective

Western lifestyle contributes to an overt increase in the prevalence of metabolic anomalies including diabetes mellitus (DM) and obesity. Prevalence of DM is rapidly growing worldwide, affecting many individuals in both developing and developed countries. DM is correlated with the onset and development of complications with diabetic nephropathy (DN), diabetic cardiomyopathy (DC) and diabetic neuropathy being the most devastating pathological events. On the other hand, Nrf2 is a regulator for redox balance in cells and accounts for activation of antioxidant enzymes. Dysregulation of Nrf2 signaling has been shown in various human diseases such as DM. This review focuses on the role Nrf2 signaling in major diabetic complications and targeting Nrf2 for treatment of this disease. These three complications share similarities including the presence of oxidative stress, inflammation and fibrosis. Onset and development of fibrosis impairs organ function, while oxidative stress and inflammation can evoke damage to cells. Activation of Nrf2 signaling significantly dampens inflammation and oxidative damage, and is beneficial in retarding interstitial fibrosis in diabetic complications. SIRT1 and AMPK are among the predominant pathways to upregulate Nrf2 expression in the amelioration of DN, DC and diabetic neuropathy. Moreover, certain therapeutic agents such as resveratrol and curcumin, among others, have been employed in promoting Nrf2 expression to upregulate HO-1 and other antioxidant enzymes in the combat of oxidative stress in the face of DM.

Betulinic acid protects against cardiotoxicity of the organophosphorus pesticide chlorpyrifos by suppressing oxidative stress, inflammation, and apoptosis in rats

The widespread application of organophosphorus (OP) pesticides can affect the environment as well as the animal and human health. Chlorpyrifos (CPF) is a broad-spectrum OP pesticide used in agriculture and can cause several toxic effects in which oxidative stresses and inflammation play a key role. This study aimed to evaluate the protective activity of betulinic acid (BA), an antioxidant and anti-inflammatory pentacyclic triterpene, against CPF cardiotoxicity in rats. The rats were divided into four groups. CPF (10 mg/kg) and BA (25 mg/kg) were orally administered for 28 days, and blood and heart samples were collected. CPF-administered rats showed an increase in serum cardiac troponin I (cTnI), creatine kinase (CK)-MB, and lactate dehydrogenase (LDH), accompanied with multiple myocardial tissue alterations. Lipid peroxidation (LPO), nitric oxide (NO), nuclear factor-kappaB (NF-κB), interleukin (IL)-6, IL-1β, and tumor necrosis factor (TNF)-α were increased, and antioxidant were decrease in CPF-administered rats. BA ameliorated cardiac function markers and tissue injury, decreased LPO, NO, NF-κB, and proinflammatory cytokines, and increased antioxidants. In addition, BA decreased proapoptosis markers, and increased B-cell lymphoma (Bcl)-2, IL-10, Nrf2, and HO-1 in the heart of CPF-treated rats. In conclusion, BA protected against cardiotoxicity in CPF-administered rats by mitigating oxidative stress, inflammation, and apoptosis, and enhanced Nrf2 and antioxidants.

Betulin prevents high fat diet-induced non-alcoholic fatty liver disease by mitigating oxidative stress and upregulating Nrf2 and SIRT1 in rats

Non-alcoholic fatty liver disease (NAFLD) is a common chronic hepatic disorder characterized by hepatic lipid accumulation. This study explored the effect of betulin (BE), a terpenoid with promising antioxidant, anti-inflammatory and insulin sensitizing effects, on NAFLD induced by high fat diet (HFD). Rats received HFD and BE (15 and 30 mg/kg) for 12 weeks and blood and liver samples were collected for analyses. HFD caused hyperlipidemia, cholesterol and triglycerides accumulation in the liver, hepatocellular ballooning, fibrosis, insulin resistance (IR), lipid peroxidation (LPO), and NF-kB p65 upregulation. BE ameliorated serum and liver lipids, blood glucose, and insulin, liver LPO, prevented steatosis and fibrosis, suppressed NF-kB p65 and enhanced antioxidants in HFD-fed rats. BE downregulated ACC1 and FAS, and upregulated Nrf2, HO-1 and SIRT1 in the liver of HFD-fed rats. In silico investigations revealed the binding affinity of BE towards NF-kB, Keap1, HO-1 and SIRT1. In conclusion, BE attenuated HFD-induced NAFLD by ameliorating hyperlipidemia, IR, lipogenesis, liver lipid accumulation, and oxidative stress. The protective effect of BE was associated with enhanced Nrf2/HO-1 signaling and SIRT1.

Nanocarriers for the Delivery of Neuroprotective Agents in the Treatment of Ocular Neurodegenerative Diseases

Retinal neurodegeneration is considered an early event in the pathogenesis of several ocular diseases, such as diabetic retinopathy, age-related macular degeneration, and glaucoma. At present, there is no definitive treatment to prevent the progression or reversal of vision loss caused by photoreceptor degeneration and the death of retinal ganglion cells. Neuroprotective approaches are being developed to increase the life expectancy of neurons by maintaining their shape/function and thus prevent the loss of vision and blindness. A successful neuroprotective approach could prolong patients' vision functioning and quality of life. Conventional pharmaceutical technologies have been investigated for delivering ocular medications; however, the distinctive structural characteristics of the eye and the physiological ocular barriers restrict the efficient delivery of drugs. Recent developments in bio-adhesive in situ gelling systems and nanotechnology-based targeted/sustained drug delivery systems are receiving a lot of attention. This review summarizes the putative mechanism, pharmacokinetics, and mode of administration of neuroprotective drugs used to treat ocular disorders. Additionally, this review focuses on cutting-edge nanocarriers that demonstrated promising results in treating ocular neurodegenerative diseases.

Fibrosis: Types, Effects, Markers, Mechanisms for Disease Progression, and Its Relation with Oxidative Stress, Immunity, and Inflammation

Most chronic inflammatory illnesses include fibrosis as a pathogenic characteristic. Extracellular matrix (ECM) components build up in excess to cause fibrosis or scarring. The fibrotic process finally results in organ malfunction and death if it is severely progressive. Fibrosis affects nearly all tissues of the body. The fibrosis process is associated with chronic inflammation, metabolic homeostasis, and transforming growth factor-β1 (TGF-β1) signaling, where the balance between the oxidant and antioxidant systems appears to be a key modulator in managing these processes. Virtually every organ system, including the lungs, heart, kidney, and liver, can be affected by fibrosis, which is characterized as an excessive accumulation of connective tissue components. Organ malfunction is frequently caused by fibrotic tissue remodeling, which is also frequently linked to high morbidity and mortality. Up to 45% of all fatalities in the industrialized world are caused by fibrosis, which can damage any organ. Long believed to be persistently progressing and irreversible, fibrosis has now been revealed to be a very dynamic process by preclinical models and clinical studies in a variety of organ systems. The pathways from tissue damage to inflammation, fibrosis, and/or malfunction are the main topics of this review. Furthermore, the fibrosis of different organs with their effects was discussed. Finally, we highlight many of the principal mechanisms of fibrosis. These pathways could be considered as promising targets for the development of potential therapies for a variety of important human diseases.

Flavonoids of Haloxylon salicornicum (Rimth) prevent cisplatin-induced acute kidney injury by modulating oxidative stress, inflammation, Nrf2, and SIRT1

Cisplatin (CIS) is an effective chemotherapeutic drug used for the treatment of many types of cancers, but its use is associated with adverse effects. Nephrotoxicity is a serious side effect of CIS and limits its therapeutic utility. Haloxylon salicornicum is a desert shrub used traditionally in the treatment of inflammatory disorders, but neither its flavonoid content nor its protective efficacy against CIS nephrotoxicity has been investigated. In this study, seven flavonoids were isolated from H. salicornicum methanolic extract (HSE) and showed in silico binding affinity with NF-κB, Keap1, and SIRT1. The protective effect of HSE against CIS nephrotoxicity was investigated. Rats received HSE (100, 200, and 400 mg/kg) for 14 days followed by a single injection of CIS. The drug increased Kim-1, BUN, and creatinine and caused multiple histopathological changes. CIS-administered rats showed an increase in renal ROS, MDA, NO, TNF-α, IL-1β, and NF-κB p65. HSE prevented tissue injury, and diminished ROS, NF-κB, and inflammatory mediators. HSE enhanced antioxidants and Bcl-2 and downregulated pro-apoptosis markers. These effects were associated with downregulation of Keap1 and microRNA-34a, and upregulation of SIRT1 and Nrf2/HO-1 signaling. In conclusion, H. salicornicum is rich in flavonoids, and its extract prevented oxidative stress, inflammation, and kidney injury, and modulated Nrf2/HO-1 and SIRT1 signaling in CIS-treated rats.

Attenuation of hyperglycemia-associated dyslipidemic, oxidative, cognitive, and inflammatory crises via modulation of neuronal ChEs/NF-κB/COX-2/NOx, and hepatorenal functional deficits by the Tridax procumbens extract

Tridax procumbens (cotton buttons) is a flowering plant with a medicinal reputation for treating infections, wounds, diabetes, and liver and kidney diseases. The present research was conducted to evaluate the possible protective effects of the T. procumbens methanolic extract (TPME) on an experimentally induced type 2 diabetes rat model. Wistar rats with streptozotocin (STZ)-induced diabetes were randomly allocated into five groups of five animals each, viz., a normal glycemic group (I), diabetic rats receiving distilled water group (II), diabetic rats with 150 (III) and 300 mg/kg of TPME (IV) groups, and diabetic rats with 100 mg/kg metformin group (V). All treatments were administered for 21 consecutive days through oral gavage. Results: Administration of the T. procumbens extract to diabetic rats significantly restored alterations in levels of fasting blood glucose (FBG), body weight loss, serum and pancreatic insulin levels, and pancreatic histology. Furthermore, T. procumbens significantly attenuated the dyslipidemia (increased cholesterol, low-density lipoprotein-cholesterol (LDL-C), triglycerides, and high-density lipoprotein (HDL) in diabetic rats), serum biochemical alterations (alanine transaminase (ALT), aspartate transaminase (AST), alanine phosphatase (ALP), blood urea nitrogen (BUN), creatinine, uric acid, and urea) and full blood count distortion in rats with STZ-induced diabetes. The TPME also improved the antioxidant status as evidenced by increased superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), and decreased malondialdehyde (MDA); and decreased levels of cholinesterases (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)), and proinflammatory mediators including nuclear factor (NF)-κB, cyclooxygenase (COX)- 2, and nitrogen oxide (NOx) in the brain of rats with STZ-induced diabetes compared to rats with STZ-induced diabetes that received distilled water. However, TPME treatment failed to attenuate the elevated monoamine oxidases and decreased dopamine levels in the brain of rats with STZ-induced diabetes. Extract characterization by liquid chromatography mass spectrometry (LC-MS) identified isorhamnetin (retention time (RT)= 3.69 min, 8.8%), bixin (RT: 25.06 min, 4.72%), and lupeol (RT: 25.25 min, 2.88%) as the three most abundant bioactive compounds that could be responsible for the bioactivity of the plant. In conclusion, the TPME can be considered a promising alternative therapeutic option for managing diabetic complications owing to its antidiabetic, antihyperlipidemic, antioxidant, and anti-inflammatory effects in rats with STZ-prompted diabetes.

Rosmarinic acid mitigates chlorpyrifos-induced oxidative stress, inflammation, and kidney injury in rats by modulating SIRT1 and Nrf2/HO-1 signaling

Chlorpyrifos (CPF) is a widely used broad-spectrum pesticide with multi-organ toxic effects. Oxidative stress was found to play a role in the deleterious effects of CPF, including nephrotoxicity. This study investigated the protective effect of the antioxidant polyphenol rosmarinic acid (RA) against CPF-induced kidney injury, with an emphasis on oxidative injury, inflammation, SIRT1, and Nrf2/HO-1 signaling. Rats received 10 mg/kg CPF and 25, 50, and 100 mg/kg RA orally for 28 days, and the samples were collected for analysis. CPF increased serum urea and creatinine and kidney Kim-1 and caused several histopathological alterations. ROS, MDA, NO, NF-κB p65, TNF-α, and IL-1β were elevated in the kidney of CPF-intoxicated rats. RA ameliorated kidney function markers, prevented tissue injury, suppressed ROS, MDA, and NO, and downregulated NF-κB p65, TNF-α, and IL-1β in CPF-intoxicated rats in a dose-dependent manner. RA decreased Bax, caspase-3, oxidative DNA damage, and Keap1, boosted antioxidant enzymes and Bcl-2, and upregulated Nrf2, HO-1, and SIRT1 in CPF-administered rats. Molecular docking simulation revealed the binding affinity of RA toward NF-κB, Keap1, HO-1, and SIRT1. In conclusion, RA prevented CPF nephrotoxicity by attenuating oxidative stress, inflammation, and apoptosis and upregulating SIRT1 and Nrf2/HO-1 signaling.

Genistin modulates high-mobility group box protein 1 (HMGB1) and nuclear factor kappa-B (NF-κB) in Ehrlich-ascites-carcinoma-bearing mice

Cancer is the world's second-largest cause of death. Although there are numerous cancer treatment options, they are typically uncomfortable owing to side effects and ineffectual due to increased resistance to traditional anti-cancer medications or radiation therapy. A key method in cancer treatment is to target delayed/inhibited inflammation and apoptosis, which are very active areas of research. Natural chemicals originating from plants are of particular interest because of their high bioavailability, safety, few side effects, and, most importantly, cost-effectiveness. Flavonoids have become incredibly common as anti-cancer medications, with promising findings as cytotoxic anti-cancer agents that cause cancer cell death. Isolated compound (genistin) was evaluated for in vitro antiproliferative activity against breast cancer cell line (MCF-7 and MDA-MB-231). The compound exhibited good cytotoxic activities against both cell lines. In vivo antiproliferative efficacy was also investigated in Ehrlich's ascites carcinoma (EAC). Compared to the control group, genistin revealed a significant decrease in tumor weight, volume, high-mobility group box1 (HMGB1), and nuclear factor-kappa B (NF-κB) contents. On the other hand, B-cell lymphoma 2 (Bcl-2) contents increase suggesting an anti-inflammatory and anti-apoptotic activity through inhibition of HMGB1 signaling and activating the Bcl-2 pathway.

Primaquine activates Keratin 7 to treat diabetes and its complications

Background

The global prevalence of type 2 diabetes mellitus (T2DM) raises the rates of its complications, such as diabetic nephropathy and cardiovascular diseases. To conquer the complications, new strategies to reverse the deterioration of T2DM are urgently needed. In this project, we aimed to examine the hypoglycemic effect of primaquine and explore its specific target.

Methods

In vitro T2DM insulin resistance model was built in HepG2 cells to screen the potential anti-diabetic chemicals. On the other hand, the potential protein targets were explored by molecular docking. Accordingly, we chose C57BL/6 N mice to establish T2DM model to verify the effect of the chemicals on anti-hyperglycemia and diabetic complications.

Results

By targeting the Keratin 7 (K7) to activate EGFR/Akt glucose metabolism signaling pathway, primaquine poses a potent hypoglycemic effect. The level of acetyl-CoA is enhanced markedly, supporting that primaquine upregulates the aerobic glycolysis. Moreover, primaquine ameliorates kidney function by reducing the secretion of urinary proteins and creatinine, especially for the urea nitrogen which is significantly decreased compared to no-treatment T2DM mice. Notably, primaquine restores the level of plasma low-density lipoprotein cholesterol (LDL-C) nearly to normal, minimizing the incidence of cardiovascular diseases.

Conclusions

We find that primaquine may reverse the dysregulated metabolism to prevent diabetic complications by stimulating EGFR/Akt signaling axis, shedding new light on the therapy of T2DM.

Graphical abstract

Insulin resistance is characterized by reduced p-Akt and glucose metabolism, dominated by anaerobic glycolysis. Primaquine activates the complex made of K7 and EGFR, further stimulating Akt phosphorylation. Then, p-Akt promotes the aerobic glucose metabolism and upregulates Ac-CoA to mobilize TCA cycle, improving insulin sensitivity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40200-022-01135-8.

7-hydroxycoumarin modulates Nrf2/HO-1 and microRNA-34a/SIRT1 signaling and prevents cisplatin-induced oxidative stress, inflammation, and kidney injury in rats

The kidneys are vulnerable to toxicity and acute kidney injury (AKI) is the main adverse effect associated with the clinical use of the chemotherapeutic agent cisplatin (CIS). Oxidative stress and inflammation are implicated in CIS nephrotoxicity. In this study, the effect of the antioxidant 7-hydroxycoumarin (7-HC) against CIS-induced renal intoxication was evaluated. Rats received 7-HC (25, 50, and 100 mg/kg) orally for 14 days and CIS (7 mg/kg) at day 15, and samples were collected 3 days after CIS administration. CIS increased serum urea, creatinine and kidney injury molecule (Kim)-1, caused multiple histopathological changes and increased renal reactive oxygen species (ROS), malondialdehyde (MDA), nitric oxide (NO), NF-κB p65, iNOS, and pro-inflammatory cytokines. 7-HC dose-dependently prevented kidney dysfunction and tissue injury and suppressed ROS and inflammatory mediators. 7-HC boosted renal antioxidants and Bcl-2 while decreased Bax and caspase-3 expression in CIS-administered rats. In addition, 7-HC downregulated Keap-1 and microRNA-34a and upregulated Nrf2, NQO-1, HO-1, and SIRT1. Molecular docking revealed the binding affinity of 7-HC towards NF-κB, Keap-1, and SIRT1. In Conclusion, 7-HC prevented CIS nephrotoxicity by attenuating tissue injury, oxidative stress, inflammation, and apoptotic cell death. The protective efficacy of 7-HC was associated with inhibiting NF-κB and Keap-1, and modulating Nrf2/HO-1 and microRNA34a/Sirt1 signaling.

Effect of angiotensin II pathway inhibitors on post-surgical adhesion band formation: a potential repurposing of old drugs

BACKGROUND

In this study we investigated the therapeutic potential of angiotensin II pathway inhibitors in attenuating post-surgical adhesion band formation in tendon injury.

METHOD

We assigned 30 Wistar albino rats to 5 groups, including negative control, positive control, sham, Telmisartan- and Enalapril-treated groups (n=6). Telmisartan and Enalapril at a dose of 10 mg/kg were administered intraperitoneally for 21 days. Hematoxylin-Eosin, and Masson's trichrome staining were used to measure the inflammatory cell accumulation and collagen deposition in the Achilles tendon tissue sections. Oxidative stress markers were analyzed in tissue samples by spectrophotometric methods. Properties of Achilles tendon adhesions were compared based on Tang and Ishiyama scoring systems in the presence and absence of angiotensin II pathway inhibitors.

RESULTS

Telmisartan and Enalapril reduced severity, length, and density of surgical-induced tendon adhesion at site of injury (***p < 0.001). Our results showed that administration of angiotensin II pathway inhibitors decreased infiltration of inflammatory cells to the injured area (*p < 0.05) and suppressed inflammation by regulating oxidative stress markers including MDA (***p < 0.001), total thiol (***p < 0.001), CAT (***p < 0.001), and SOD (***p < 0.001), in post-operative Achilles tendon tissues. Significant lower collagen deposition and formation of fibrotic tissues was seen in Telmisartan- and Enalapril-treated groups as detected by Masson's trichrome staining which correlated with a decrease in quantity (**p < 0.01) and grading of fibrosis score (***p < 0.001), in adhesive tissues. Moreover, inhibition of angiotensin II pathway could also ameliorate mechanical properties including ultimate load (***p < 0.001), and ultimate stress (*p < 0.05) in injured Tendons.

CONCLUSION

Our results showed that ssuppression of inflammation and fibrosis are two mechanisms by which Telmisartan and Enalapril elicit potent protective responses post Achilles tendon injuries.

NLRP3-mediated pyroptosis in diabetic nephropathy

Diabetic nephropathy (DN) is the main cause of end-stage renal disease (ESRD), which is characterized by a series of abnormal changes such as glomerulosclerosis, podocyte loss, renal tubular atrophy and excessive deposition of extracellular matrix. Simultaneously, the occurrence of inflammatory reaction can promote the aggravation of DN-induced kidney injury. The most important processes in the canonical inflammasome pathway are inflammasome activation and membrane pore formation mediated by gasdermin family. Converging studies shows that pyroptosis can occur in renal intrinsic cells and participate in the development of DN, and its activation mechanism involves a variety of signaling pathways. Meanwhile, the activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome can not only lead to the occurrence of inflammatory response, but also induce pyroptosis. In addition, a number of drugs targeting pyroptosis-associated proteins have been shown to have potential for treating DN. Consequently, the pathogenesis of pyroptosis and several possible activation pathways of NLRP3 inflammasome were reviewed, and the potential drugs used to treat pyroptosis in DN were summarized in this review. Although relevant studies are still not thorough and comprehensive, these findings still have certain reference value for the understanding, treatment and prognosis of DN.

The potential mechanisms of Macrocystis pyrifera polysaccharides mitigating type 2 diabetes in rats

Our previous studies have proved that the anti-digestive polysaccharide from Macrocystis pyrifera possesses potential hypoglycemic and lipid-lowering activities; however, its potential mechanisms for improving diabetes have not been elucidated. The current study was aimed to determine the anti-diabetic effects and possible mechanisms of Macrocystis pyrifera polysaccharides (MPP) in diabetic rats. After 8-week MPP treatment, the serum profiles, gut bacteria composition and relative gene expressions of rats were determined. MPP administration effectively ameliorated the diabetic symptoms, dyslipidemia, liver and kidney damage, oxidative stress and chronic inflammation in diabetic rats. In addition, MPP treatment could also notably improve the microbial dysbiosis by increasing the beneficial bacteria and decreasing a bacterial pathogen in the diabetic rats. The RT-qPCR analysis indicated that MPP intervention significantly up-regulated the IRS/PI3K/AKT signaling pathway and down-regulated the relative expressions of glucose-6-phosphatase (G-6-Pase), phosphoenolpyruvate carboxykinase (PEPCK), acetyl-CoA carboxylase (ACC), hydroxymethylglutaryl CoA reductase (HMGCR) and sterol regulatory element binding protein 1c (SREBP-1c) in diabetic rats. These results demonstrated that MPP had the potential to be exploited as functional foods or pharmaceutical supplements for preventing and treating diabetes.

How to Restore Oxidative Balance That Was Disrupted by SARS-CoV-2 Infection

Coronavirus 2019 disease (COVID-19) is caused by different variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which emerged in December of 2019. COVID-19 pathogenesis is complex and involves a dysregulated renin angiotensin system. Severe courses of the disease are associated with a dysregulated immunological response known as cytokine storm. Many scientists have demonstrated that SARS-CoV-2 impacts oxidative homeostasis and stimulates the production of reactive oxygen species (ROS). In addition, the virus inhibits glutathione (GSH) and nuclear factor erythroid 2-related factor 2 (NRF2)-a major antioxidant which induces expression of protective proteins and prevents ROS damage. Furthermore, the virus stimulates NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasomes which play a significant role in inducing a cytokine storm. A variety of agents with antioxidant properties have shown beneficial effects in experimental and clinical studies of COVID-19. This review aims to present mechanisms of oxidative stress induced by SARS-CoV-2 and to discuss whether antioxidative drugs can counteract detrimental outcomes of a cytokine storm.

Nrf2 Activation in Chronic Kidney Disease: Promises and Pitfalls

The nuclear factor erythroid 2-related factor 2 (Nrf2) protects the cell against oxidative damage. The Nrf2 system comprises a complex network that functions to ensure adequate responses to redox perturbations, but also metabolic demands and cellular stresses. It must be kept within a physiologic activity range. Oxidative stress and alterations in Nrf2-system activity are central for chronic-kidney-disease (CKD) progression and CKD-related morbidity. Activation of the Nrf2 system in CKD is in multiple ways related to inflammation, kidney fibrosis, and mitochondrial and metabolic effects. In human CKD, both endogenous Nrf2 activation and repression exist. The state of the Nrf2 system varies with the cause of kidney disease, comorbidities, stage of CKD, and severity of uremic toxin accumulation and inflammation. An earlier CKD stage, rapid progression of kidney disease, and inflammatory processes are associated with more robust Nrf2-system activation. Advanced CKD is associated with stronger Nrf2-system repression. Nrf2 activation is related to oxidative stress and moderate uremic toxin and nuclear factor kappa B (NF-κB) elevations. Nrf2 repression relates to high uremic toxin and NF-κB concentrations, and may be related to Kelch-like ECH-associated protein 1 (Keap1)-independent Nrf2 degradation. Furthermore, we review the effects of pharmacological Nrf2 activation by bardoxolone methyl, curcumin, and resveratrol in human CKD and outline strategies for how to adapt future Nrf2-targeted therapies to the requirements of patients with CKD.